Apparatus for drafting textile fibers



' Oct. 16, 1956 c. D. BRANDT ET AL 2,766,486

APPARATUS FOR DRAFTING TEXTILE FIBERS Filed June 10, 1953 .1 M 7 a H ATTY.

United States Patent Offiice 2,766,486 Patented Oct. 16, 1956 APPARATUS FOR DRAFTING TEXTILE FIBERS Carl D. Brandt, Whitinsville, and John S. Dudley, Douglas, Mass., assignors to Whitin Machine Works, Whitinsville, Mass., a corporation of Massachusetts Application June 10, 1953, Serial No. 360,762

1 Claim. (Cl. 19-130) This invention relates to the drafting of fibers in textile machines, such as combers or drawing frames. In such machines, drafting conditions vary for different fibers and particularly for fibers of different lengths, and the usual apparatus, if well adapted for one length of fiber, is not commonly adapted for a substantially different length.

It is the general object of our invention to provide improved drafting apparatus which may be readily adapted to the drafting of textile fibers of widely different lengths.

A further object is to provide drafting apparatus in which the change in setting required for a substantial change in fiber length is very easily and quickly accomplished.

We further provide drafting apparatus so organized as to maintain an exceptionally high degree of control over the fibers during the drafting operation, thus producing a sliver or strand having exceptional uniformity.

Our invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claim.

A preferred form of the invention is shown in the drawings, in which Fig. 1 is a sectional side elevation of our improved drafting apparatus as set for the drafting of short fibers, such as cotton;

Fig. 2 is a sectional side elevation similar to Fig. 1 but showing the apparatus set for the drafting of long fibers, such as Worsted or long synthetics; and

Fig. 3 is a sectional front elevation, taken along the line 33 in Fig. 2.

Referring to the drawings, we have shown our improved drafting apparatus as comprising back rolls and 11, intermediate rolls 14, and 16, and front rolls 17, 18, 19 and 20.

The bottom back roll 10 is mounted in bearing blocks 24 secured on frame members F by clamping screws 25. The back top roll 11 is guided for vertical movement in open slots or recesses 26 in th blocks 24.

The intermediate bottom rolls 14 and 16 are rotatable in bearings in intermediate bearing blocks 30, clamped to the frames F by screws 32, and the intermediate top roll 15 is guided for vertical movement in open slots or recesses 33 in the blocks 30.

The front bottom rolls 17 and 19 are rotatable in bearings in bearing blocks 40, secured to the frames F by clamping screws 41. The front top roll 18 is mounted for near-vertical movement in slots or recesses 42 in the blocks 40 and normal to the common tangent of the bottom rolls 17 and 19. The second or supplementary front top roll 20 is similarly guided for movement in vertical slots or recesses 44.

The frames F are preferably longitudinally grooved to receive guiding portions 50 (Fig. 3) on the bottom of the blocks 24, 30 and 40, and the frames F are also slotted to permit longitudinal movement of the clamping screws 25 and 32 for adjustment of the blocks 24 and 30 relative to the front bearing blocks 40 and also relative to each other.

All of the bottom rolls are positively rotated by the usual gear connections (not shown) at such relative speeds as to produce a definite draft between the back and intermediate rolls and an additional draft between the intermediate and front rolls as is customary, and the bottom rolls 10, 14, 17 and 19 are preferably longitudinally grooved or fluted as indicated and as is customary. The bottom roll 16 is preferably a smooth-surfaced cylindrical roll.

All of the top rolls are covered with suitable cushioning material, such as synthetic rubber or a relatively soft plastic. The covering of the intermediate top roll 15 is less resilient than the covering of the other top rolls 11, 18 and 20.

Pressure is applied to the top rolls in any usual or convenient manner, as by weights or springs. Hooks or hangers 55 (Fig. 3) may be used to apply the tension of such weights or springs to the top rolls.

In Fig. 1, our improved drafting apparatus is shown as set for drafting cotton or other relatively short fibers, and it will be noted that the intermediate bearing blocks and rolls are closely adjacent to the front bearing blocks and rolls, so that there is a relatively short distance between the nip of the intermediate rolls 15 and 16 and the nip of the front rolls 17 and 18.

Exceptionally uniform drafting is accomplished by the provision of the two bottom intermediate rolls 14 and 16, both engaging the intermediate top roll 15, and also by the provision of the two bottom front rolls 17 and 19, both engaging the front top roll 18. In this way, a more positive control of the fiber and the drafting thereof is attained.

In the drafting of long fibers, however, and particularly of long synthetic fibers, fibers of exceptional length are occasionally encountered, and for this reason the intermediate bottom roll 16 is provided with a smooth or unfluted surface, so that such exceptionally long fibers may be drawn out of the intermediate rolls without breakage.

The second or supplementary front top roll 20 has no drafting function, but is effective in preventing any fibers from being lapped around the top roll 18. The roll 21) also assists in holding the sliver firmly against th front bottom roll 19, so that the sliver will be directed outwardly and downwardly thereby.

With drafting apparatus constructed as above described, the drafting of fibers of substantially difierent lengths may be successfully accomplished and the apparatus may be very quickly and easily adapted for drafting fibers of different lengths.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claim, but what we claim is:

In a drafting apparatus, a pair of top and bottom back rolls, two adjacent bottom intermediate rolls, a single top intermediate roll engaging both of said bottom intermediate rolls, a pair of bottom front rolls, a single top front roll engaging both of said bottom front rolls, said back, intermediate, and front bottom rolls being driven at relative speeds effective to produce draft between the back and intermediate rolls and additional draft between the intermediate and front rolls the bottom intermediate roll nearer said bottom front rolls having a relatively smooth fiber-engaging surface and allowing relatively long fibers to be drafted without breakage at said roll, and the bottom back roll, the rear bottom intermediate roll, and both bottom front rolls having relatively rough drafting surfaces.

References Cited in the file of this patent UNITED STATES PATENTS Bisinger et a1. Aug. 23, 1955 FOREIGN PATENTS Great Britain of 1860 Great Britain of 1858 Great Britain of 1896 France Dec. 29, 1923 

